Helicopter



FIG. 1 is a right side elevational view of the helicopter showing our new design;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof.

Portions of the rotor blades in FIGS. 5 and 6 are shown broken away for convenience of illustration. 

The ornamental design for a helicopter, as shown and described. 